CAS Installation Failed – The Value Cannot Be Null. Parameter Name: Key
During and Exchange 2010 installation recently, I received the following message during the Client Access Server installation:
Client Access Role Failed
Error:
The following error was generated when "$error.Clear(); $thisServer = Get-ExchangeServer $RoleFqdnOrName; $adSiteId = $thisServer.Site; $pureMailboxServersFqdns = Get-ExchangeServer | Where {$adSiteId -eq $_.Site -and $_.IsMailboxServer -and -not $_.IsClientAccessServer} | ForEach {$_.Fqdn}; Get-MailboxDatabase | Where { ($pureMailboxServersFqdns -contains $_.RpcClientAccessServer) -and ($adSiteId -eq (Get-ExchangeServer $_.Server).Site)} | Set-MailboxDatabase -RpcClientAccessServer $thisServer" was run: "Value cannot be null.
Parameter name: key".
Value cannot be null. Parameter name: key
Elapsed Time: 00:01:22
After searching around for a while I came across a Microsoft message board where I found the answer. The error was caused because remnants of a previous installation of Exchange 2010 were still lingering around, this particular error caused because the installer found the unattached ghost database from the previous Exchange 2010 installation. What solved my problem was to open adsiedit and remove the old database remants located beneath ConfigurationCN=Configuration,DC=<org>,DC=<suf>CN=ServicesCN=Microsoft ExchangeCN=<org>CN=Administrative GroupsCN=Exchange Administrative Group (FYDIBOHF23SPDLT)CN=Databases.
Before doing this, be sure you know that you are deleting the correct database entries, if you delete incorrect entries you will be causing irreperable damage to your current Exchange environment.
Sources:
Thank you
Thank you very much, This helped me and saved me a lot of hair pulling
Okay i finally found this entry but there was only one cn entry in there. It was just lou-mailbox that is the current exchange 2007 box that was broken. I know before exchange 2010 was trying to get installed but i did not know what the name of the server was. Is there a way I can save that because i do not want to delete. I am unsure if that is db is exchange 2010 or not. Is there a way to tell ?
A quick first step (not sure if you tried this or not) would be to do an Organizational Health Check from the Exchange Console. You should be able to see Exchange databases and the servers they are connected to. Please refer to this thread: http://social.technet.microsoft.com/Forums/en-US/exchange2010/thread/e0ce7d25-a621-470f-be7b-a19288e2ba9f?prof=required